[hatari-devel] Memory, Falcon and TT (24 vs 32 bits computers)

[Eero Tamminen]

Hi,

On keskiviikko 19 tammikuu 2011, Thomas Huth wrote:
> I don't think that you've got to change here much. The old UAE core
> already has the address_space_24 configuration variable, which should
> theoretically be able to switch between 24 and 32 bit mode.
> The magic is here only done in uae-cpu/memory.c: When in 24 bit mode
> (which is the only working mode in Hatari right now), the same address
> banks are mapped multiple times already, so that it does not matter
> which byte has been put in the highest 8 bits of the the address.
> 
> I think you've only got the change both memory.c files a little bit if
> you want to support Fast-RAM (beyond the 16 MB barrier) emulation.

There's also the OS memory initialization code in stMemory.c and most
of the Hatari code uses the macros & inlines from stMemory.h to access
memory:
$ grep -l STMemory_ *.c */*.[ch]
bios.c
blitter.c
fdc.c
gemdos.c
memorySnapShot.c
mfp.c
stMemory.c
tos.c
vdi.c
xbios.c
includes/stMemory.h
cpu/hatari-glue.c
debug/breakcond.c
debug/debugcpu.c
debug/debugInfo.c
debug/evaluate.c
uae-cpu/hatari-glue.c

Can applications on TT/CT60 etc. use addresses pointing to TT/Fast-RAM
e.g. in their GEMDOS calls?

If yes, either stMemory.h macros & functions need to be modified too
or alternatively a lot of Hatari code needs to be changed to use AUE core
functions instead...


	 - Eero